What is in this article?:
- Early season stresses affecting Louisiana corn
- Zinc deficiency
- Cold temperatures have been the biggest challenge for Louisiana corn producers this season.
- LSU AgCenter specialists say producers need to watch corn closely for symptoms of stress and damage.
- Nitrogen management is also crucial in cold, wet growing conditions, they say.
CORN WITH frost damage, however growth point is still active.
With the 2012 growing season a distant memory, many are remembering how unpredictable and challenging early springs in Louisiana can be. Unlike many states around the Mid-South, Louisiana was fortunate enough to get a large portion of its corn crop planted within the recommended time frame. However this year’s corn crop has experienced its share of stressful conditions since planting, many of which may have had a significant effect on yield.
Potentially, the biggest challenges during the early part of the 2013 growing season have been the cold temperatures, which have slowed germination and growth of young corn plants. In addition to overall cooler temperatures, near or below freezing temperatures experienced in the later part of March caused anywhere from very sporadic to widespread damage, especially in northern Louisiana.
Much of the effect of the late March freeze was typically cosmetic or corn exhibited only slight die-back of the exposed leaves because they were between germination and V2. Corn plants experienced similar, but less severe conditions due to temperatures in the mid- to high-30s over the evenings of April 19 and April 20. Furthermore, a lot of corn is now at a much more vulnerable stage nearing V5-6, where the growth point is no longer protected underneath the soil surface.
While high yield loss or overall corn stand loss not likely with these conditions, corn needs to be strictly monitored by checking to ensure the growth point is still active and alive. To check, take the corn in question and split the corn lengthwise down the stem and identify the growth point. A healthy growth point will be firm and white with a yellow tint, while an injured or dead growth point will be completely brown or appear to have a brown tint.
In addition to the direct damage temperatures are causing, cooler temperatures have intensified many other stressful conditions such as bird damage, nutrient deficiencies, etc. Many of these are due to slower root and aboveground growth compared to other years. Once favorable conditions return, normal growth recommences, but overall effects on growth and yield are not known.
For the second year in a row, several areas throughout Louisiana are reporting yellow striped corn on newly emerged leaves at very early leaf stages. While these symptoms are very distinct, they can potentially be attributed to different problems.